If you put the words Mein Kampf into the search function of the Guardian's online bookshop you get two editions offered for sale: one at £8.99 and another at £16. The first is not introduced in any way, the second carries the following text:

"Hitler's infamous political tract was first published in 1925-26 and has been widely translated since. This edition contains a detailed introduction which analyses Hitler's background, his ideology and his ruthless understanding of political power."

That is a factual description of a book which has the power to shock to this day. It espouses a rabidly antisemitic view of the world among other things. I have never read the whole book. However, I am entirely convinced that it is a book that should be available to be read because it has an important lesson from history; suppression would only lend an unjustified mystique. In this area waders or a wet suit are more suitable than a standard pair of wellington boots to navigate through the depths of this subject.

Should every book legally published be available in the Guardian's online bookshop? This is where it becomes even more difficult. Part of me says, yes. I am opposed to the suppression of books and believe in the power of readers to make rational and intelligent decisions. Bring things into the light. But even where the sale of a book is legal, there will always be a selection process. Where the Guardian is involved in that selection process, it has the right to do what all good bookshops do and select what it offers according to its own principles such as when it is publishing its own books. Where the Guardian is not involved in selecting the title, then it has a duty to tell potential shoppers that that is the case.

Last week the Guardian's online bookshop removed a title from the automated stocklist that it receives from a book wholesaler. The wholesaler is blameless; it runs a feed of the topselling 5,000 books into the Guardian and several other national newspapers.

Gilad Atzmon's The Wandering Who? was removed because of the controversy it has caused. Atzmon says he is anti-Zionist but he has been accused of making antisemitic remarks, including past praise for the "prophetic qualities" of the Protocols of the Elders of Zion, a falsified tract purporting to show plans for Jewish domination of the world that was written by agents of Tsarist Russia.

In addition to any moral decision on a book's content, there is a technical problem. If the Guardian removes a book, it automatically disappears from the other shared newspapers' electronic feeds of the list of 5,000 bestselling books.

After strong protests last November about the inclusion of Atzmon's book in the Guardian's online bookshop, we removed it from the electronic feed but it was later restored on our bookshop lists and therefore other newspapers' feeds. One reason was the technological problem but the others were considered to be broader issues. At the time Guardian executives considered that:

• Books containing offensive material will continue to be published and the Guardian is in the position of having to decide what is and what is not acceptable in response to future challenges.

• If a book is removed, the impression may be created that the Guardian "approves" of all the other books on the Guardian's bookshop feed.

"In addition to our recommendations, our browsable selection of books also includes a feed of the top 5,000 bestselling titles through independent booksellers (not including Amazon) as supplied by Bertrams. Inclusion in this automated feed does not necessarily denote recommendation by GNM."

Now the book is off the list again following renewed protests. It will remain so. The Guardian will work to improve the processes around the automated feed, but it will be impossible to hand-pick every title in the bookshop. Like all online booksellers, the Guardian makes available almost every title in the English language (currently around 200,000).

The process of making the decision has been messy, uncomfortable and, at times, confusing.